In this study we will emmpirically derive the principles of effective therapy of minimal residual malignant disease following induction of complete remission. In the BN x Lewis rat we have achieved prolonged unmaintained complete remission of a myelocytic leukemia following a timed sequential regimen of arabinosyl cytosine closely analogous to effective remission induction therapy of human myelocytic leukemia. We will attempt to prolong these remissions with cytotoxic and non-cytotxic complementary therapy. Intensive cytotoxic therapy in early remission (consolidation), in late remission (late intensification) and low dose continuous therapy (maintenance) will be compared to no therapy for effect on duration of remission and survival. A number of non-cytotoxic chemical agents known to stimulate host response to malignancy will also be tested in this model (levamisole, thiabendazole, amphotericin B, pyran copolymer). The experiments are designed to permit conclusions regarding the optimum dose, timing and sequence of effective agents.